Module 14 - Sickle Scalers / Module 15 - Universal Curets

Sickle Scaler

A periodontal instrument used to remove calculus deposits from the crowns of the teeth
*NOT TO BE USED ON ROOT SURFACES

Purpose and Use of Sickle Scaler

*Removal of large sized deposits above the gingival margin
*Medium to large sized deposits just slightly belowte gingival margin
*Fine calclus from under contact points

Working-End Design of a Sickle Scaler

1)Pointed back
2)Pointed tip
3)Triangular cross section
4)Two cutting edges
5)Face is perpendicular

Anterior Sickle Scalers

Limited to the use on anterior treatment sextants
*Are often single-ended instruments b/c only one working-end is needed to instrument the crowns of anterior teeth
*It is common to combine two different anterior sickles on a double-ended instrument

Posterior Sickle Scalers

Designed for use on posterior sextants, but may also be used on anterior teeth
*Usually two posterior sickles are paired on a double -ended instrument (the working-ends are mirror images of one another)
Ex: The Jacquette 34 is paired w/ the Jacquette 35 (

Examples of Sickle Scaler Instruments

*Anterior sickle scalers---OD-1, Jacquette 30, Jacquette 33, Nevi 1, Whiteside-2, USC-128, Towner-U15, Goldman-H6, and Goldman-H7
*Posterior sickle scalers---Jacquette 34/35, Jacquette 14/15, Jacquette 31/32, Nevi 2, Ball 2/3, Mecca 11/12, and the Cataton

Calculus Removal stroke with a Sickle Scaler

- Apply pressure w/ index & thumb, stable fulcrum against tooth
- Tip-third of cutting edge is adapted
- 70-80 degree angulation, the lower shank must be tilted toward the tooth surface to achieve correct angulation
- Moderate to firm pressure against the

Steps for Calculus removal w/ Hand-activated Instruments (Sickle scaler/Universal curet)

1. Me
2. My Patient
3. My equipment
4. My non-dominant hand
5. My dominant hand
6. My finger rest
7. My adaptation - adapt leading-third
8. My angulation - 70-80 degrees
9. My stabilization - strong fulcrum
10. My activation - Short strokes away from JE
1

Inner cutting edge (sickle scaler)

Cutting edge that is closer to the instrument handle, used to instrument on distal surfaces

Outer cutting edge (sickle scaler)

Cutting edge is farther from the instrument handle, used to instrument the facial, lingual, and mesial surfaces

Cross section

Triangular cross section; this design limits use to above the gingival margin because the pointed tip and back could cause tissue trauma

Working-End

Pointed back and tip
Two cutting edges per working-end

Face

Face is perpendicular to the lower shank so that cutting edges are level w/ one another; level cutting edges mean that the lower shank must be tilted slightly toward the tooth surface to establish correct angulation

Application

ANTERIOR TEETH- only one single-ended instrument is needed
POSTERIOR TEETH - one double ended instrument is needed

Primary functions

Removal of medium- to large- sized calculus deposit.
Excellent for calculus on the
1. proximal surfaces of anterior crowns and
2. enamel surfaces apical to the contact areas of posterior teeth

Universal Curet

A periodontal instrument used to remove small-and medium-size calculus deposits from the crowns and roots of the teeth

Universal Curets can be used supragingivally and subgingivally -

on crown and root surfaces

A universal curet is usually

A double-ended instrument w/ paired, mirror-image working-ends

Design Characteristics of Universal instruments

-paired, mirror image working ends
-two cutting edges - both used
-terminal shank is perpendicular to face of blade - 90 degree angle
-can be used on all surfaces of teeth in all areas of mouth

Unique Design Characteristics ...

-rounded back
-rounded toe
-two cutting edges per working-end
-semicircular in cross section

Is a sickle scaler used subgingivally or supragingivally?

Supragingivally

On what surfaces should sickle scalers not be used on?

Root Surfaces

What kind of back does the sickle scaler have?

Pointed; newer has rounded

In cross section, how does the sickle scaler appear?

Triangular

How many cutting edges does the sickle scaler have per end?

Two

Is the face perpendicular or parallel to the lower shank?

Perpendicular

How many working ends are needed to instrument anterior teeth?

One

Can posterior sickle scalers be used on anterior teeth?

Yes

The working ends are _____ of each other on a posterior sickle scaler

Mirror Images

Why wouldn't we want to use the sickle subgingivally?

Pointed tip and back could cause tissue trauma

On a sickle, are the cutting edges level with one another?

Yes

Since the cutting edges are level on a sickle scaler, what do you have to do to establish correct angulation?

Lower shank must be tilted toward the tooth surface

What size of calculus deposits is the sickle scaler used for?

Medium to large sized calculus deposits

The sickle scalers are excellent for removal on what two surfaces?

1) proximal surfaces of anterior crowns
2) enamel surfaces apical to the contact areas of posterior teeth

Does the nevi 4 have a flexible or rigid working-end and shank?

Rigid

Which nevi is excellent to use on pediatric patients?

Nevi 3

What surfaces is the nevi 1 disk end used for?

Supragingival use on the lingual surfaces of anterior teeth

Does the Nevi 1 have a flexible or rigid shank?

Rigid

What part of the cutting edge is adapted to the tooth for the sickle scalers?

Tip-third

What angulation is used for sickle scalers?

70-80

What kind of lateral pressure is used for calculus removal when instrumenting with a sickle scaler?

Moderate to firm

When using a sickle, vertical strokes are most commonly used where?

Anterior teeth and mesial and distal surfaces of posterior teeth

When using a sickle, where are oblique strokes most commonly used?

Facial and lingual surfaces of posterior teeth

When instrumenting with a sickle, where are horizontal strokes used?

Line angles of posterior teeth and the midlines of the facial or lingual surfaces of anterior teeth

What is the stroke number for sickle scalers?

Strokes should be limited to areas where calculus is present; use the minimum number or strokes needed to remove calculus deposits

Correct technique for the sickle involves placing the cutting edge against the proximal surface with the working-end positioned where?

Btn the tooth and the papillary gingiva

The sickle's correct working-end is selected when the lower shank is perpendicular or parallel to the distal surface?

Parallel

The functional shank is up and over the tooth or down and around?

Up and over

The inner cutting edge of the sickle scaler is used to instrument what surfaces?

Distal surfaces

The outer cutting edge is used to instrument what surfaces?

Facial, lingual, and mesial surfaces

Which cutting edge is farther from the instrument handle?

Outer cutting edge

Which cutting edge is closer to the instrument handle?

Inner cutting edge

How many total cutting edges does a posterior sickle scaler have?

4 = (2 per each working-end)

What is the angle of the face of the working end of a sickle scaler?

90 degrees

Where should the lower shank be for the posterior sickle scaler?

Parallel to the distal surface.

The face is ___________ to the lower shank

Perpendicular

Design characteristics of universal curet of Barnhardt 1-2

-used for removal of light to moderate subgingival calculus
-curved with flexible shank
-adapts to all areas of mouth

How many cutting edges does a universal Curet have?

2-cutting eges, continuous around the toe

What is unique about the cutting edge on area specific curets?

One edge is more curved
Only one cutting edge on area specific curets

Describe the face and base of Curets?

The face is flat, the base is rounded

The cross section of a curet is what?

Semi-circular

The back and toe of a curet are what?

Rounded

Curets can be?

Paired, mirrored or doubled with a sickle

Where can a Curet scale?

Supra and subgingivally

Why can a Curet go subgingivally?

Because its back is rounded, and the cutting edge is contionously round

Two purposes of a curet:

Scaling (calculus removal) and Root Planing

What is the purpose of root planing?

Designed to remove cementum or surface dentin that is rough, contains calculus, or contaminated with microorganisms

What degree of calculus do curets remove?

Light to moderate
Light= Universal curet
Moderate= Gracey curet

What is root debridement?

Instrumentation stroke used to remove Residual calculus deposits, bacterial plaue, and by-products from root surfaces

Two types of universal curets?

Barnhart 5/6
SN137
Columbia(SC) 13/14

Barnhart 5/6 is used on which teeth? Columbia 13/14?

Both used on posterior

SN137 is used on what type of teeth?

Anterior

What kind of Gracey is used on mesials of teeth?

Gracey 11/12, Gracey 15/16

What kind of Gracey is used on posterior surfaces?

Gracey 13/14, Gracey 17/18

What kind of Gracey is used on mesials and distals of anterior teeth?

Gracey 1/2

On area specific curets, what is the relationship of the face to the lower shank?

Face is at a 70* angle to the lower shank, with one cutting edge lower than the other in relationship to the lower shank

The lower cutting edge of a Gracey curet is ___, meaning the cutting edge is automatically at the correct angle when what?

Self-angulated, correct angle when the lower shank is parallel to the tooth surface being cleaned

Each instrument curet is limited to?

Use on certain teeth and certain surfaces

The cutting edges of curets are ___, to enhance ______

each cutting edge is rounded, to enhance adaptation to rounded root surfaces and root concavities

Difference of face to lowershank between sickle scaler, universal curet, area-specific curet

Sickle scaler = 90*
Universal curet = 90*
Area specific= 70*

The lower cutting edge tilts ____ from the lower shank

Tilts away from the lower shank
(the other cutting edge is too close to the lower shank to be used)

How to identify proper cutting edge on area specific curets:

1. Look directly at the toe(facing you)
2. Put lower shank perpendicular to the floor
3. lower cutting edge = working cutting edge

When you insert the Curet, the face should be what?

Flat to tooth during insertion into sulcus (face closed)

Ideal angulation for Curet?

45-90* angulation
but 70-80* is ideal

When to use large vs. smaller curets

large= heavy calculus
small= fine calculus and root planing

What kind of curet would you use for root planing?

Small

What type of stroke is used for Curets?

Pull stroke (vertical and oblique)

Why is the curet the instrument of choice for subgingival sclaing and root debridement?

Adapts well to cervical areas and root anatomy

Shank for anterior vs. posterior curets?

Anterior= straight
Posterior = angled

When the working end is placed against the ____surface and tilts towards it, you have the right end

When it is placed against facial of tooth

Stroke for curets

Short, precise strokes across tooth
roll handle slightly to maintaing adaptation of the toe-third to tooth

Visual Cue: Correct working end is selected when lower shank is ____ to the distal surface, and functional shank goes ______

Parallel, up and over the tooth

Strokes should be ____ on posterior scaling, and _____ across mesial surface

Strokes should be vertical on posterior, and obliue across mesial

The toe-third of a curet is also known as?

Leading-third